This study is designed to evaluate an experimental powdered formula (NeoCare 22) containing a greater protein to energy ratio and higher concentrations of protein and minerals to determine if preterm infants will have greater catch-up growth and bone mineralization over a 12- month period than similar infants fed a standard term powdered formula (Similac 20). The study will test the following hypothesis: growth and skeletal mineralization of healthy preterm infants fed NeoCare powdered formula will be no greater than for infants fed Similac powdered formula during the first 12 months post-discharge. The primary variables of interest include weight and length increments and total body skeletal mass. Protein and mineral biochemical indices, body composition (lean body mass, %body fat), and feeding tolerance will be secondary variables. NeoCare formula contains 30% more protein, 50% more Ca and P, and 75% more zinc than Similac; both are iron fortified. 30 infants will be enrolled at the Baylor site, a total of 68 are expected to complete the multicenter study. From the time they reach 1.8 kg body weight prior to hospital discharge, study infants will be fed NeoCare (NC) or similac with Iron (SWI) powdered formula as the only milk feeding to 12 months post-discharge. Infants will be enrolled into the study when they reach 1.8 kg and are completely fed orally. They will be randomized to study group (NC vs. SWI) and all powdered formulas and mixing equipment will be provided to the hospital and families by Ross Laboratories. After study entry, there will be 5 scheduled study wisits, 8,16,26,40, & 52 wk after hospital discharge, to measure growth. Three-day milk intake records and feeding tolerance diaries will be collected in-hospital and at all visits. Serum albumin, prealbumin, retinol-binding protein, Ca, P, alkaline phosphatase, and osteocalcin will be measured at study entry and at 16 and 52 wk. Total body mineralization using DEXA (dual energy x-ray absorptiometry, QDR 2000, Hologic) and lean body mass using [40]K counting will be measured at study entry and at 8,16, and 52 wk while the infants are sleeping but not sedatd. Infant behavior, feeding and stool paterns, and formula satisfaction questionnaires wil be completed by the parents at 8 and 16 wk.